△C分析中的常见问题与对策

△C已被广泛应用于各类油气田的地球化学找矿勘查和远景评价中,针对样品测试过程中的预处理、热释、色谱分离和检测多个步骤中的常见问题,提出解决对策。

Cloning and Sequence Analysis of Lactate Dehydrogenase C(LDH-C)Gene from Black-lipped Pika in Western Sichuan Plateau

[Objective] The aim was to lay a foundation for research of contraceptive rodenticide with LDH-C4 as target protein. [ Method] EST sequence of LDH-C gene from black-lipped pika was cloned by PCR with degenerate primers; then the full length open reading frame （ORF） and 3＇UTR sequence were cloned by RACE technique. [ Result] The full length cDNA was 1 498 bp containing an ORF of 996 bp and a 3＇UTR of 486 bp. The ORF encoded a polypeptide of 332 amino acids. The alignment of LDH-C gene ORF nucleotide sequences from different species showed that the gene was conserved even between large taxons. The phylogenic tree showed that black-lipped pika LDH-C was closer to prima- tes and artiodactyla than to rodents. [Conclusion] cDNA sequence of LDH-C gene from black-lipped pika was cloned successfully.

Reliability Analysis of a Mixed Redundant Model in C 3I System

Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute system. The reliability and availability equations of MRM were deduced. Results and Conclusion Compared with several other reliability models, it has obvious effect upon improving the system reliability. The effect? cost rate is very high among these models. The model can be used in reliability design, evaluation and check of C 3I system. Only a little attached cost is needed to improve C 3I system reliability effectively.

SCGM(1,m)_c model with time-lag and its application in deformation analysis

Originated in the early 1990s, SCGM(1, m ) c model has enjoyed widespread application in the fields of urban planning, society economy prediction and modal control in recent years. However, none of these applications have taken account of time lag effects in the modeling process. Aiming at overcoming the defect, the authors introduced time lag items into SCGM(1, m ) c model and developed a SCGM(1, m ) c model with time lag, then discusses in detail some principal problems in the model, such as parameters estimation, model verifying, model prediction, etc. The model was used on a real slope monitoring project and compared with the conventional SCGM(1, m ) c model. The results show an improvement of average models precision from 1.321 to 0.238 and total average of relative prediction errors from 12.41% to 7.98% when the modeling data length ranges from 29 to 48 in the slope monitoring case.

Markers of systemic inflammation and colorectal adenoma risk: Meta-analysis of observational studies

To perform a meta-analysis of observational studies on inflammatory markers levels and occurrence of colorectal adenoma.METHODSPubMed and EMBASE databases were searched until March 2016 for the articles reporting on the circulating levels of inflammatory markers, including: C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) and risk of colorectal adenoma. Random-effects models were used to calculate summary odds ratios (ORs) with 95%CIs for the highest vs lowest category of exposure. Heterogeneity was assessed by using the Q test and I2 statistic. Subgroup analyses were also performed to test for potential source of heterogeneity.RESULTSA total of 14 case-control studies were included. Ten studies on CRP including a total of 3350 cases and 4168 controls showed non-significant summary (OR = 1.23, 95%CI: 0.98-1.54; I2 = 54%, Pheterogeneity = 0.01) in the general analysis, but significant increased odds when considering only advanced adenoma (OR = 1.59, 95%CI: 1.09-2.32; I2 = 44%, Pheterogeneity = 0.15). Subgroup and stratified analyses revealed a potential influence of smoking status and aspirin use on the association between CRP levels and colorectal adenoma. Five studies examined the association between circulating levels of TNF-α and colorectal adenoma risk, including a total of 1,568 cases and 2,832 controls. The summary OR for the highest vs the lowest category of exposure was 1.00 (95%CI: 0.77-1.29). The relationship between circulating IL-6 levels and colorectal adenoma risk was investigated in 7 studies including a total of 1936 cases and 3611 controls. The summary OR for the highest vs the lowest category of exposure was 1.19 (95%CI: 0.92-1.55).CONCLUSIONSummary of current evidence suggests a positive association of CRP levels and advanced colorectal adenoma risk. The role of potential confounding factors should be further evaluated.

Molecular Cloning and Sequence Analyses of cDNAs Encoding Seven C-type Lectin-like Protein Subunits from Daboia russellii siamensis

Total mRNA was extracted from a venom gland of snake Daboia russellii siamensis following the manufacturer＇s protocol of the PolyATtract System 1000 kit purchased from Promega Biotech. cDNAs encoding C-type lectins were amplified by RT-PCR and subcloned into a pMD18-T vector. Fourteen positive clones were selected for nucleotide sequencing and seven cDNAs encoding various snake venom C-type lectin-like protein precursors, designated as DRS-L1, DRS-L2, DRS-L3, DRS-L4 DRS-L5, DRS-L6 and DRS-L7, were obtained. Amino acid sequences of these proteins were deduced and each contains a carbohydrate recognition domain. Of all the deduced protein sequences, only DRS-L1 seemed to represent a closer sequence similarity to α subunits of other known snake venom C-type lectin-like proteins using the BLAST program. Homology comparison combined with analysis of cysteine position indicate that DRS-L1 and DRS-L2 are probably the light chain LC2 and LC1 of factor X activator from Daboia russellii siamensis venom, respectively. DRS-L3 and DRS-L4 might be the β subunits of higher molecular weight C-type lectin-like proteins while DRS-L5 and DRS-L6 might be β subunits of lower molecular weight C-type lectin-like proteins. DRS-L7 might be the β subunit of a platelet membrane glycoprotein Ib-binding protein similar to echicetin.

Cloning and Differential Expression Analysis of FaGF14-B and FaGF14-C Genes in Tall Fescue

[Objective] The differential expression analysis was performed for FaGF14- B and FaGF14-C genes in tall fescue so as to provide certain basis for follow-up functional analysis of genes. [Method] The sequence fragments of FaGF14-B and FaGF14-C obtained from reverse transcription were used as templates, and the full- length cDNA sequences of FaGF14-B and FaGF14-C were amplified using the 5＇ RACE use 3＇RACE techniques. They were named as FaGF14-B and FaGF14-C, and used for nucleic acid sequence analysis, encoded protein analysis, protein con- served domain analysis, phylogenetic analysis and differential expression analysis. [Result] The FaGF14-B gene has a full length of 1 548 bp. It has a complete open reading frame （ORF, 449-1 228 bp）, and encodes a protein composed of 261 amino acids. The FaGF14-C gene has a full length of 1 250 bp. It also has a complete open reading frame （ORF, 66-848 bp）, and encodes a protein composed of 261 amino acids. The GF14-B and GF14-C proteins all have a typical domain 14-3-3, and their secondary structures all contain 9 conserved co-helical structures and non-conserved N- and C- terminals. The phylogenetic analysis showed that the FaGF14-B and FaGF14-C from tall rescue have high similarities with GF14 protein from gramineous plants, and they are divided into the same clade with closer ge- netic relationship. The real-time fluorescence quantitative PCR analysis showed that the expression of FaGF14-B and FaGF14-C genes is all sensitive to nitrogen stress. [Conclusion] This study will lay a theoretical basis for further screening of low nitrogen-tolerant genes and breeding of low nitrogen-tolerant grass germplasms.

Aluminum production by carbothermo-chlorination reduction of alumina in vacuum

Aluminum production by carbothermo-chlorination reduction of alumina in vacuum was investigated by XRD, SEM, EDS and thermodynamic analysis. Thermodynamic calculations indicate that AlCl（g） generated by carbothermo-chlorination process among Al2O3-C-AlCl3 system should be at 1377-1 900K （100 Pa） and AlCl（g） will disproportionate into aluminum and AlCl3（g） below 950-1 050 K at 10-102 Pa. Experimental results demonstrate that Al4O4C and Al4C3 begin to be formed by Al2O3-C system over 1698 K （40-150Pa）. It is Al4O4C and Al4C3 but not Al2O3-C that participate in the carbothermic-chlorination reaction. Temperature for AlCl（g） generated by Al4O4C-AlCl3-C, Al4C3-Al2O3-AlCl3 and Al4OC-Al4C3-Al2O3-AlCl3-C system is 1 703-1853 K （40-150 Pa）. Aluminum metal is produced by AlCl（g） disproportionation process below 933 K. The average purity of aluminum metal reaches 95.32%, which has perfect crystallization and uniform grain size.

Study on the ultraviolet-visible spectral feature of tobacco leaves by pattern recognition

In order to differentiate regions, varieties, and parts of tobacco leaves, two pattern recognition methods through pattern classification modeling were developed based on the comprehensive information of ultraviolet-visible spectroscopy （UV-VIS） by employing one-way analysis of variance （ANOVA1） and wave range random combination （WRRC） technology from MATLAB. This proposed classification method has never been reported previously and the instrument and operation for this method is much more convenient and efficient than previous reported classification methods. The result of this paper demonstrated that the spectral features extracted by ANOVAI and WRRC methods could be used to differentiate tobacco leaves with different patterns. The ANOVAI method had a training recognition rate range of 75.00-87.50%,4 and a validation recognition rate range of 57.14-100%. The WRRC method had a training recognition rate range of 75.00-94.12% and a validation recognition rate range of 66.67-100%. The ANOVAI method is more convenient and efficient in model developing, while the WRRC method utilizes fewer model variables and is more robust.

SEQUENCE ANALYSIS OF THE NS5 REGION OF GBVC/HGV AND DETECTION OF THE VIRUS BY REVERSE TRANSCRIPTASE PCR

GBV C/HGV is a newly identified virus associated with human hepatitis In this study, the nucleotide sequences of the partial NS5 gene of GBV C/HGV derived from sera of 8 Chinese patients were determined The nucleotide homology among the 8 isolates were 92% on average On the basis of sequence analysis, two sets of oligonucleotide primers derived from highly conserved region of GBV C/HGV NS5 gene were designed to establish both sensitive and specific nested PCR for detection of GBV C/HGV RNA 253 Chinese patients were examined for the virus RNA GBV C/HGV RNA positive rates in patients infected with HBV, HCV and patients with chronic non B,non C hepatitis were 18 4%, 19 8% and 8 9% respectively This result suggested that HBV,HCV and GBV C/HGV shared the same transmission risk factors 8 patients with GBV C/HGV and HCV coinfection were retrospectively observed for the response to interferon Coinfection with GBV/HGV did not negatively influence the responsiveness of HCV, and GBV C/HGV was sensitive to interferon to a certain degree

Adaptive WNN aerodynamic modeling based on subset KPCA feature extraction

In order to accurately describe the dynamic characteristics of flight vehicles through aerodynamic modeling, an adaptive wavelet neural network (AWNN) aerodynamic modeling method is proposed, based on subset kernel principal components analysis (SKPCA) feature extraction. Firstly, by fuzzy C-means clustering, some samples are selected from the training sample set to constitute a sample subset. Then, the obtained samples subset is used to execute SKPCA for extracting basic features of the training samples. Finally, using the extracted basic features, the AWNN aerodynamic model is established. The experimental results show that, in 50 times repetitive modeling, the modeling ability of the method proposed is better than that of other six methods. It only needs about half the modeling time of KPCA-AWNN under a close prediction accuracy, and can easily determine the model parameters. This enables it to be effective and feasible to construct the aerodynamic modeling for flight vehicles.

Development of two-axis control index table driven by direct drive motors

The stability and reliability of a tilting index table should be considered at the design stage. A design method for the lightweight and improvement of the stability of the structure in a tilting index table was proposed using a commercial analysis program, ANSYS Workbench 12, by analyzing the static-thermal characteristics of the developed high-accuracy tilting index table at its design stage. The results of the performed structural analysis show that the maximum stress is generated at the stock tail part. An optimum design for the stock tail part was carried out to reduce the maximum stress and deformation. Also, the design variables were determined by considering the support of the stock tail part for the C-axis body. In the comparison of the results before and after the optimization, the maximum deformation and stress are improved by 2.8% and 8%, respectively.

PCR AMPLIFICATION, MOLECULAR CLONING,DNA SEQUENCE ANALYSIS AND IMMUNO/PROTECTION IN BALB/C MICE OF THE 33 kDa ENDOFLAGELLAR PROTEIN OF L.INTERRORGANS SEROVAR LAI

A pair of oligonucleotide primers were designed to amplify the endoflagella gene of L. Interrogans serovar lai. An approximately 840 bp fragment was generated with PCR and inserted into plasmid pUC8,after the fragment and pUC8 were digested respectively with BamHI and PstI. A recombinant plasmid (designated as pLF1 ) was obtained. SDS-PAGE analysis indicated that a 33 kDa was expressed in E. Coli JM103 harboring pLF1 and the expression level of the protein was 11 % of the total bacterial soluble proteins. Western blot analysis showed that the protein band could be recognized by the antiserum against the endoflegella (Axial filament ) of Leptospira interrt,gans serover lai. Nucleotide sequence data showed an open reading frame encoding 282 aminoacids residues,corresponding to a protein of molecular weight 33. 6kDa. Comparison of the deduced endoflagellar subunit protein (flaB) amino acid sequence with flagellins from other bacteria revealed a high level of identity with the Trehoema pallid um flaB proteins. Immunization/protection experiment was performed on the model of BALB/C mice and showed that there was higher survival rate in the group JM103-pLE1 than in the group JM103-pUC8.

Synthesis of Large-Area, Few-Layer Graphene on Iron Foil by Chemical Vapor Deposition

We demonstrate a simple and controllable way to synthesize large-area, few-layer graphene on iron substrates by an optimized chemical vapor deposition （CVD） method using a mixture of methane and hydrogen. Based on an analysis of the Fe-C phase diagram, a suitable procedure for the successful synthesis of graphene on Fe surfaces was designed. An appropriate temperature and cooling process were found to be very important in the synthesis of highly crystalline few-layer graphene. Graphene-based field-effect transistor （FET） devices were fabricated using the resulting few-layer graphene, and showed good quality with extracted mobilities of 300-1150 cm2/（V.s）.

Accessibility analysis in manufacturing processes using visibility cones

Accessibility is a kind of important design feature of products,and accessibility analysis has been acknowledged as a powerful tool for solving computational manufacturing problems arising from different manufacturing processes.After exploring the relations among approachability,accessibility and visibility,a general method for accessibility analysis using visibility cones (VC) is proposed.With the definition of VC of a point,three kinds of visibility of a feature,namely complete visibility cone (CVC),partial visibility cone (PVC) and local visibility cone (LVC),are defined.A novel approach to computing VCs is formulated by identifying C-obstacles in the C-space,for which a general and efficient algorithm is proposed and implemented by making use of visibility culling.Lastly,we discuss briefly how to realize accessibility analysis in numerically controlled (NC) machining planning,coordinate measuring machines (CMMs) inspection planning and assembly sequence planning with the proposed methods.

DC faults ride-through capability analysis of Full-Bridge MMC-MTDC System

Full-Bridge Modular Multilevel Converter(FBMMC) has strong ability to ride through serious DC faults,thus it is very suitable for multi-terminal flexible HVDC applications.However,no references have reported the locating and isolating of DC faults and corresponding DC faults ride-through capability evaluation index.This paper introduces the topology mechanism of FBMMC and its loss reduction operation mode,theoretically certifies that the universal decoupled control strategy of Voltage Source Converter(VSC) and the similar modulation strategies of Half-Bridge MMC(HBMMC) can be applied to FBMMC for constructing complete closed-loop control system.On the basis of the existing DC faults locating and isolating schemes of 2-level VSC based Multi-Terminal HVDC(VSC-MTDC) system and the particularity of FBMMC,this paper proposes the DC faults wire selection "handshaking" method of the FBMMC-MTDC system,and proposes the DC Fault Ride-Through Capability Index(DFRTI) for evaluating the DC faults suppressing capability of the VSC-MTDC systems,including FBMMC-MTDC.Simulations of FBMMC-MTDC in PSCAD/EMTDC validate the correctness and effectiveness of the proposed control strategy and evaluation index.

Effects of Huangqi and bear bile on recurrent parotitis in children:a new clinical approach

Objective:To evaluate the pharmacological effects of traditional Chinese medicine,bear bile capsule and Huangqi granule,on recurrent parotitis in children.Methods:In this prospective,controlled,and randomized study,a total of 151 young children were divided into three groups:Group A included massaging the children's parotid region and melting vitamin C in their mouth daily;Group B included swallowing bear bile capsule and Huangqi granule daily;and Group C included massages and vitamin C as prescribed in Group A,and traditional Chinese medicine as prescribed in Group B.Children were treated individually for one month and then a follow-up study was conducted for 1 to 3.5 years.Analysis of variance(ANOVA) and Ridit analysis were employed for statistical analysis.Results:The recurrence rate decreased in every group,but was significantly more in Groups B and C when compared to Group A.The recurrences significantly decreased(P<0.01) in Group B and their recovery rate was as high as 63%,significantly better than those of the other groups(P<0.01).Conclusions:Huangqi and bear bile could be a novel clinical approach for treating recurrent parotitis in children.